//:: call :(before "End Initialize Op Names(name)") put(name, "e8", "call disp32"); :(scenario call_disp32) % Reg[ESP].u = 0x64; == 0x1 # op ModR/M SIB displacement immediate e8 a0 00 00 00 # call function offset at 0x000000a0 # next EIP is 6 +run: call imm32 0x000000a0 +run: decrementing ESP to 0x00000060 +run: pushing value 0x00000006 +run: jumping to 0x000000a6 :(before "End Single-Byte Opcodes") case 0xe8: { // call disp32 relative to next EIP int32_t offset = imm32(); trace(90, "run") << "call imm32 0x" << HEXWORD << offset << end(); //? cerr << "push: EIP: " << EIP << " => " << Reg[ESP].u << '\n'; push(EIP); EIP += offset; trace(90, "run") << "jumping to 0x" << HEXWORD << EIP << end(); break; } //: :(scenario call_r32) % Reg[ESP].u = 0x64; % Reg[EBX].u = 0x000000a0; == 0x1 # op ModR/M SIB displacement immediate ff d3 # call function offset at EBX # next EIP is 3 +run: call to r/m32 +run: r/m32 is EBX +run: decrementing ESP to 0x00000060 +run: pushing value 0x00000003 +run: jumping to 0x000000a3 :(before "End Op ff Subops") case 2: { // call function pointer at r/m32 trace(90, "run") << "call to r/m32" << end(); int32_t* offset = effective_address(modrm); push(EIP); EIP += *offset; trace(90, "run") << "jumping to 0x" << HEXWORD << EIP << end(); break; } :(scenario call_mem_at_r32) % Reg[ESP].u = 0x64; % Reg[EBX].u = 0x10; == 0x1 # code segment # op ModR/M SIB displacement immediate ff 13 # call function offset at *EBX # next EIP is 3 == 0x10 # data segment a0 00 00 00 # 0xa0 +run: call to r/m32 +run: effective address is 0x10 (EBX) +run: decrementing ESP to 0x00000060 +run: pushing value 0x00000003 +run: jumping to 0x000000a3 //:: ret :(before "End Initialize Op Names(name)") put(name, "c3", "return from most recent unfinished call"); :(scenario ret) % Reg[ESP].u = 0x60; == 0x1 # code segment # op ModR/M SIB displacement immediate c3 == 0x60 # data segment 10 00 00 00 # 0x10 +run: return +run: popping value 0x00000010 +run: jumping to 0x00000010 :(before "End Single-Byte Opcodes") case 0xc3: { // return from a call trace(90, "run") << "return" << end(); EIP = pop(); trace(90, "run") << "jumping to 0x" << HEXWORD << EIP << end(); break; }